Motorcycle frame



FIG. 1 is a front perspective view of a motorcycle frame showing our new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is an elevational view of one side thereof, the other side being a mirror image thereof;

FIG. 4 is a rear view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a motorcycle frame, as shown and described. 